Merge pull request swiftlang#31932 from rintaro/ide-completion-rdar62479469

[CodeCompletion] Handle variadic parameter in expr context analysis

Author: rintaro

lib/IDE/ExprContextAnalysis.cpp

@@ -656,21 +656,22 @@ class ExprContextAnalyzer {
           if (memberDC && ty->hasTypeParameter())
             ty = memberDC->mapTypeIntoContext(ty);
 
+          bool canSkip =
+              paramList && (paramList->get(Pos)->isDefaultArgument() ||
+                            paramList->get(Pos)->isVariadic());
+
           if (paramType.hasLabel() && MayNeedName) {
-            bool isDefaulted = paramList &&
-                               paramList->get(Pos)->isDefaultArgument();
             if (seenArgs.insert({paramType.getLabel(), ty.getPointer()}).second)
-              recordPossibleParam(&paramType, !isDefaulted);
-            if (isDefaulted)
-              continue;
+              recordPossibleParam(&paramType, !canSkip);
           } else {
             auto argTy = ty;
             if (paramType.isInOut())
               argTy = InOutType::get(argTy);
             if (seenTypes.insert(argTy.getPointer()).second)
               recordPossibleType(argTy);
           }
-          break;
+          if (!canSkip)
+            break;
         }
         // If the argument position is out of expeceted number, indicate that
         // with optional nullptr param.
@@ -980,11 +981,13 @@ class ExprContextAnalyzer {
         case ExprKind::Binary:
         case ExprKind::PrefixUnary:
         case ExprKind::Assign:
-        case ExprKind::Array:
         case ExprKind::Dictionary:
         case ExprKind::If:
         case ExprKind::UnresolvedMember:
           return true;
+        case ExprKind::Array:
+          return (!Parent.getAsExpr() ||
+                  !isa<VarargExpansionExpr>(Parent.getAsExpr()));
         case ExprKind::Tuple: {
           auto ParentE = Parent.getAsExpr();
           return !ParentE ||

test/IDE/complete_call_arg.swift

@@ -106,6 +106,10 @@
 
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYPATH_THUNK_BASE | %FileCheck %s -check-prefix=KEYPATH_THUNK_BASE
 
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=VARIADIC_1 | %FileCheck %s -check-prefix=VARIADIC_1
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=VARIADIC_2 | %FileCheck %s -check-prefix=VARIADIC_2
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=VARIADIC_3 | %FileCheck %s -check-prefix=VARIADIC_2
+
 var i1 = 1
 var i2 = 2
 var oi1 : Int?
@@ -848,3 +852,19 @@ func testKeyPathThunkInBase() {
 // KEYPATH_THUNK_BASE-DAG: Decl[EnumElement]/ExprSpecific/TypeRelation[Identical]:     baz[#SimpleEnum#]; name=baz
 // KEYPATH_THUNK_BASE: End completions
 }
+
+func testVariadic(_ arg: Any..., option1: Int = 0, option2: String = 1) {
+    testVariadic(#^VARIADIC_1^#)
+// VARIADIC_1: Begin completions
+// VARIADIC_1-DAG: Decl[FreeFunction]/CurrModule: ['(']{#(arg): Any...#}, {#option1: Int#}, {#option2: String#}[')'][#Void#];
+// VARIADIC_1-DAG: Decl[GlobalVar]/CurrModule:    i1[#Int#];
+// VARIADIC_1: End completions
+    testVariadic(1, #^VARIADIC_2^#)
+// VARIADIC_2: Begin completions
+// VARIADIC_2-DAG: Pattern/ExprSpecific:          {#option1: Int#}[#Int#];
+// VARIADIC_2-DAG: Pattern/ExprSpecific:          {#option2: String#}[#String#];
+// VARIADIC_2-DAG: Decl[GlobalVar]/CurrModule:    i1[#Int#];
+// VARIADIC_2: End completions
+    testVariadic(1, 2, #^VARIADIC_3^#)
+// Same as VARIADIC_2.
+}